Note that all values in this statement are as compiled from data available on 2 January 2014. Subsequent quality control and the availability of additional data may result in minor changes to final values.

Overview

2013 was Australia’s warmest year since records began in 1910. Mean temperatures across Australia have generally been well above average since September 2012. Long periods of warmer-than-average days have been common, with a distinct lack of cold weather. Nights have also been warmer than average, but less so than days.

The Australian area-averaged mean temperature for 2013 was +1.20 °C above the 1961–1990 average. Maximum temperatures were +1.45 °C above average, and minimum temperatures +0.94 °C above average. Temperatures were above average across nearly all of Australia for maximum, mean and minimum temperatures, with large areas of inland and southern Australia experiencing the highest on record for each.

Australia has experienced just one cooler-than-average year (2011) in the last decade. The 10-year mean temperature for 2004–2013 was 0.50 °C above average, the equal-highest on record. Averages for each of the ten-year periods from 1995–2004 to 2004–2013 have been amongst the top ten records.

The Australian mean rainfall total for 2013 was 428 mm (37 mm below the long-term average of 465 mm). In comparison with rainfall in all years since 1900, 2013 sits close to the median or mid-point of historical observations.

Annual rainfall was below average across a large region of the inland east centred on western Queensland and extending into northern South Australia and the Northern Territory. Rainfall was above average over parts of the Pilbara and the south coast of Western Australia, as well as along the east coast and northern Tasmania.

The state of major climate influences during 2013

2013 was a neutral year for the El Niño–Southern Oscillation (ENSO), with neither El Niño or La Niña influencing Australian rainfall. Temperatures were generally slightly below normal in the eastern equatorial Pacific, but remained within neutral thresholds for the entire 12 months. In the central equatorial Pacific temperatures were very close to average. The Southern Oscillation Index (SOI) also stayed within the neutral range for most of the year with only occasional, short-lived periods above +10 (a level which would, if sustained, be indicative of La Niña).

A negative phase of the Indian Ocean Dipole (IOD) developed rapidly during late autumn, and remained in place through to the end of July before breaking down in early August. Another feature of the large-scale circulation was a strongly negative phase of the Southern Annular Mode (SAM) in late winter and spring, with the August–October value of the SAM index being the lowest since 1988. The negative IOD phase contributed to above-average rainfall over large parts of Australia in the May–July period, while the negative SAM phase from August–October contributed to above-average rainfall on the southern coastal fringe of Australia (particularly Tasmania) from August to October and dry and hot conditions in most other parts of the country, especially Queensland and New South Wales.

Frequent stretches of warm days lead to Australia's warmest year

The past year was characterised by persistent and widespread warmth. The annual mean temperature was +1.20 °C above the long-term (1961–1990) average, some +0.17 °C above the previous record set in 2005 (+1.03 °C). It was also the warmest year on record for South Australia, Western Australia and the Northern Territory. In South Australia mean temperatures were 0.41 °C above the previous record set in 2009. All other States ranked in the top four years: Queensland and New South Wales second, Victoria third and Tasmania fourth.

Both maximum and minimum temperatures were well above average; maximum temperatures were 1.45 °C above average, exceeding the previous record set in 2005 by 0.24 °C, while minimum temperatures were 0.94 °C above average, the second-highest on record. Mean and maximum temperatures were above average over nearly all of Australia and highest on record over large areas of inland and southern Australia. Minimum temperatures were also highest on record for parts of the southern mainland, with only small areas near the eastern and northern coastline recording near-average minima.

Sea surface temperatures in the Australian region

Sea surface temperatures (SSTs) around Australia were unusually warm throughout the year, with the monthly anomalies for January and February the highest on record and that for November the second-highest on record. This extends a period of sustained record-high SSTs in the Australian region since 2010.

Preliminary data, for the year to November, place SSTs for 2013 as the third-highest since 1910, 0.51 °C above the long-term average. Below-average annual SSTs have not been recorded for the Australian region since 1994; the region has seen a total rise in SSTs of approximately 1 °C since 1910, a similar value to that recorded for atmospheric warming over land.

SSTs were consistently very much above average off the western and southern coast of Australia from summer 2012–13 until May. Strong warm anomalies continued in waters to the south of the mainland throughout 2013. For the year to November, SSTs in the southern region were some 0.59 °C above average, surpassing the annual record (+0.56 °C in 1999) by 0.03 °C.

Annual mean sea surface temperature anomalies in the Australian region (compared with 1961–1990 average). The black line shows the 10-year moving average.

Recent warming trends continue

Australian land and sea surface temperatures have now warmed about 1 °C, with the majority of the warming occurring since 1950. For temperatures over land, the past ten years have been the equal-warmest on record while for sea surface temperatures the past ten years have been the warmest on record.

The Australian region warming is very similar to that seen at the global scale, and the past year emphasises that the warming trend continues. As summarised in the recent Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report, recent warming trends have been dominated by the influence of increasing greenhouse gases and the enhanced greenhouse effect.

Near-average annual rainfall, although dry in the inland east

National rainfall for 2013 was 37 mm below the long-term average, placing the annual total of 428 mm near the middle of historical observations as the 52nd-driest year on record. Tasmania and Western Australia were the only States to record above-average annual totals, with all other States and the Northern Territory recording between 79 and 92 per cent of their long-term average rainfall.

Drought conditions have affected large parts of Queensland away from the eastern coast, where rainfall has been below average since late 2012. This period included a poor wet season (December–April), leading to the emergence of significant rainfall deficiencies in the region by autumn 2013. Yearly totals were in the lowest 10 per cent of records for much of the west and inland south. Areas of below-average annual rainfall extended into northern inland New South Wales, the eastern Northern Territory and northeastern South Australia. Annual rainfall was also below average over much of the inland southeast with rainfall in the Murray–Darling Basin 24 per cent below average. Victoria saw another below-average rainfall year, meaning that rainfall for a remarkable 14 of the past 17 years has been below average.

A strip on the central coast of Western Australia, between Learmonth and Morawa, also recorded below-average annual rainfall.

Annual rainfall was substantially higher than average over much of the Pilbara and northern Interior districts of Western Australia, along the east coast between central Queensland and Sydney, in an area around Esperance on the central southern coast of Western Australia, and less significantly so in northern Tasmania, coastal Victoria and small areas of the tropical north and coastal South Australia.

National annual rainfall has been near-average during the past two years, following very high rainfall during 2010 and 2011, which was associated with La Niña conditions in the tropical Pacific Ocean.

Australian monthly rainfall totals for 2013 (blue bars), compared to the historical average (black line).

Annual mean rainfall (mm) for Australia since 1900. The black line shows the 10-year moving average.

Significant events

Heatwaves and persistent warmth

The most significant heat event of the year occurred in January (Special Climate Statement 43). An extended national heatwave began over the southwest of the continent late in December 2012 before moving into southern and eastern Australia. The heat was notable for its extent and duration, and was easily the longest continent-wide heatwave on record. Temperatures more than 10 °C above average were recorded across extensive areas of Australia until 18 January. A national daily average maximum temperature record was set on the 7th (40.30 °C) while the highest temperatures were observed on 12–13 January, exceeding 48 °C at numerous locations in inland eastern Australia. Moomba reached 49.6 °C on the 12th; this was the highest temperature recorded during 2013, the highest in South Australia since 1960 and sixth highest ever officially recorded in Australia. Hobart and Sydney also experienced their hottest days on record during the event (41.8 °C, 4 January and 45.8 °C, 18 January respectively).

A near-stationary high pressure system over the Tasman Sea brought persistent heat to southeast Australia over 2–13 March (Special Climate Statement 45). Southeast South Australia, southern Victoria and Tasmania were most affected. Melbourne experienced nine consecutive days of 30 °C or above and seven consecutive nights of 20 °C or above, both records for any time of year, while Launceston also set a record with eight consecutive days of 30 °C or above.

Unusual warmth was recorded across much of Australia from the last week of August through September (Special Climate Statement 46). The national daily average maximum temperature on 31 August (29.92 °C) was a record for winter. Warm temperatures were widespread and prolonged, especially away from the coast; a number of national, state and territory records were set for the highest temperature recorded so early in the season. The warmest day in that period was 26 September, when 29 per cent of Queensland (principally the central and southern inland) had its hottest September day on record.

Extreme heat developed over parts of Australia, particularly the eastern interior, during the last week of December. A number of locations in Queensland; including Roma, Injune, Blackall and Urandangi; had their hottest day on record on 29 or 30 December, with December monthly records at several other sites. These records, and others set as the event continued into the first days of 2014, will be discussed in a forthcoming Special Climate Statement.

Bushfires

Destructive fires occurred in southeast Australia during early 2013. The most destructive was in southeastern Tasmania when a fire started on 4 January rapidly expanded between Forcett and Dunalley (eventually exceeding 25 500 ha); 193 dwellings, significant infrastructure and 186 other buildings were destroyed or seriously damaged.

Other destructive fires burnt during January in the Warrumbungles in northwest New South Wales (exceeding 54 000 ha, 51 homes destroyed), in Victoria in the Seaton–Glenmaggie area of Gippsland (burnt 75 000 ha by month’s end, caused one direct death, destroyed 22 homes) and around Snake Valley and Carngham, west of Ballarat (destroyed nine homes). Grass fires in southern New South Wales caused heavy stock losses. Two long-lived fires each burnt more than 30 000 ha in Victoria but caused limited property damage; around Mount Hotham (January–February) and around Victoria Valley in the Grampians National Park (February–March).

A record-warm and dry winter and an early spring saw early fire activity on the east coast, culminating in the most destructive fires in the Sydney region since at least 1968. Fires burnt in the Blue Mountains in early September, followed by significant fires in mid-October; the State Mine–Mount Victoria fire burnt more than 50 000 ha to the east and south of Lithgow by month's end while the Springwood fire, northeast of Penrith, destroyed 193 homes and damaged another 122. Fifteen houses were also lost at Victoria, Lithgow, Wyong, and Balmoral. Other significant fires burnt between late September and mid-October on the Mid North Coast, between Port Stephens and Taree, destroying four homes and 17 other structures; at the Olympic Park Aquatic Centre, in Homebush; and in the north of Wollemi National Park.

Cyclones

There were a total of 10 tropical cyclones in the Australian region during the 2012–13 season, slightly below the long-term average of 11; four made landfall as cyclones, two as remnant tropical lows. The most intense at landfall was Rusty, crossing the coast near Pardoo, east of Port Hedland, as a category 4 storm on 27 February. Rusty was large and slow-moving, bringing heavy rain and strong winds to coastal regions, resulting in major flooding in Pilbara catchments and the far western Kimberley with significant rainfall extending as far south as Esperance as the decaying storm travelled south.

The remaining two landfalling cyclones crossed the coast as category 1 storms. Oswald, on the west coast of Cape York Peninsula near Kowanyama on 21 January, causing only minor wind-related impacts at landfall, but extensive flooding where the remnant low caused heavy rainfall. Peta made landfall near Karratha in Western Australia on 23 January, causing some local flooding in the Pilbara and closing Port Hedland to shipping.

Three cyclones reached the severe classification (category 3 or higher) without making landfall; Narelle (January, category 4) and Victoria (April, category 3) off Western Australia, and Sandra (March, category 3) off Queensland. None had any significant direct impact on mainland Australia, although storms associated with Narelle caused damage at Karlgarin in southwest Western Australia.

Three storms occurred late in 2013 and will form part of the count for the 2013–14 season; Alessia which made landfall south of Darwin on 24 November as a category 1 storm and again in the southern Gulf of Carpentaria on 28 November, Bruce which travelled southwest away from the coast of Java and eventually reached category 5 strength on 22 December after passing into the South West Indian Ocean basin, and category 3 Christine which crossed the coast of Western Australia near Roebourne overnight on 30–31 December. Alessia caused some localised flooding in the Top End and south of the Gulf of Carpentaria while Christine caused local flooding in the coastal northwest, generally minor wind damage, and power outages.

Flooding

The remnants of tropical cyclone Oswald brought heavy rain to much of the east coast from 21 to 29 January. Significant flooding occurred over most coastal catchments from Rockhampton to northern New South Wales, especially severe in the Burnett River catchment and around Bundaberg (Special Climate Statement 44). Damage was also caused by a number of tornadoes in the Bundaberg area, and high winds and storm surges in coastal areas.

A number of other flood events occurred during the remainder of the year, causing localised damage and interrupting transport links, but resulting in limited property inundation. Areas affected included southeast Queensland and coastal New South Wales (late February–early March), southeast Tasmania (8–9 April), the Melbourne area (1–2 June), west and central Gippsland in Victoria (12–14 June), southeast New South Wales and East Gippsland (24–26 June), and northwestern Western Australia (early and late June). Frequent heavy rain and generally above-average rainfall during the second half of 2013 led to further flooding in the northern half of Tasmania on multiple occasions during winter and spring.

Severe storms and high winds

East Coast Lows caused storm damage and coastal erosion between the central New South Wales coast and southeast Queensland on 23–26 February, with heavy rain continuing into early March causing some localised flooding, again on 24–26 May, and finally in southern coastal New South Wales and East Gippsland on 23–26 June, causing localised flooding.

A cold front passed through northern Victoria and adjacent southern New South Wales on 21 March. Associated super-cell thunderstorms caused extensive damage and injuries, with at least 20 people requiring hospital attention. Some five tornadoes were confirmed along and south of the border, with those at Violet Town and Cobram/Yarrawonga estimated to have reached at least EF3 intensity (220–266 km/h winds).

There were numerous episodes of damaging winds in southern Australia in winter and spring, most associated with the passage of strong frontal systems. Significant events involving extensive storm and wind damage, power outages and occasional tornado reports occurred on 4–6 July (southeast South Australia, Tasmania and Victoria), 15–22 July (Perth and southwest Western Australia, southeast South Australia, Tasmania), 12 August (Sydney and Melbourne), 16–18 August (southeast South Australia, southern Victoria, Tasmania), 21–22 September (southwest Western Australia from Geraldton to Busselton, including Perth), 25–26 September (southern South Australia, southern New South Wales, Victoria), 30 September–2 October (South Australia, Victoria, Tasmania, southern New South Wales) and 22 October (southeastern South Australia and Victoria). The 21–22 September event also brought significant storm surges in the Perth area with coastal and estuarine flooding, while a gust of 143 km/h at Fawkner Beacon in the early hours of 1 October was the third-strongest gust ever recorded in the Melbourne region.

Supercell thunderstorms southwest of Brisbane on the night of 12 June caused property damage in Pratten and Bony Mountain, northwest of Warwick. Heavy rain and flash flooding associated with severe thunderstorms were recorded in Sydney on 28 October, and more broadly from Sydney to southeast Queensland on the 29th. Severe thunderstorms and very large hail were also reported across southeast Queensland and Capricornia during the first half of November, with significant events on the 14th, 16th and 18th when storms also affected coastal New South Wales. There were also storms and hail north of Perth on 16 November, causing significant agricultural losses.

Globally, 2013 the sixth warmest year on record

The World Meteorological Organization (WMO) produces an estimated global mean temperature by drawing on data from three global climate datasets maintained by the UK Met Office Hadley Centre (HadCRU3v), the US National Climatic Data Centre (blended GHCNv3 and ERSST3b) and the US Goddard Institute of Space Studies (GISTEMP).
Based on preliminary data (January–November), the estimated global mean temperature for 2013 is 0.49 °C above the long-term (1961–1990) average of 14.0 °C. Using this method, 2013 ranks as the sixth-warmest year since global records commenced in 1880. No year since 1985 has recorded a below-average global mean temperature and nine of the ten warmest years have occurred in the past 12 years (2002–2013).

Accessing Australia's climate change datasets

The Bureau is responsible for collecting, managing and safeguarding Australia's climate archive. Several homogenised datasets have been developed from this archive to identify, monitor and attribute changes in the Australian climate.